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BUG: KCSAN: data-race in mem_cgroup_flush_stats_ratelimited / tick_do_update_jiffies64

read-write to 0xffffffff86e07a00 of 8 bytes by interrupt on cpu 1:
 tick_do_update_jiffies64+0x113/0x1c0 kernel/time/tick-sched.c:118
 tick_sched_do_timer kernel/time/tick-sched.c:253 [inline]
 tick_nohz_handler+0x8d/0x3d0 kernel/time/tick-sched.c:312
 __run_hrtimer kernel/time/hrtimer.c:1930 [inline]
 __hrtimer_run_queues+0x276/0x4f0 kernel/time/hrtimer.c:1994
 hrtimer_interrupt+0x261/0x850 kernel/time/hrtimer.c:2113
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1050 [inline]
 __sysvec_apic_timer_interrupt+0x5f/0x1c0 arch/x86/kernel/apic/apic.c:1067
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1061 [inline]
 sysvec_apic_timer_interrupt+0x6f/0x80 arch/x86/kernel/apic/apic.c:1061
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697
 __preempt_count_dec_and_test arch/x86/include/asm/preempt.h:95 [inline]
 __raw_spin_unlock_irq include/linux/spinlock_api_smp.h:188 [inline]
 _raw_spin_unlock_irq+0x12/0x30 kernel/locking/spinlock.c:206
 spin_unlock_irq include/linux/spinlock.h:402 [inline]
 shmem_add_to_page_cache+0x3e6/0x5b0 mm/shmem.c:928
 shmem_alloc_and_add_folio mm/shmem.c:2001 [inline]
 shmem_get_folio_gfp+0x4f3/0xd60 mm/shmem.c:2564
 shmem_fault+0xf6/0x250 mm/shmem.c:2765
 __do_fault mm/memory.c:5458 [inline]
 do_read_fault mm/memory.c:5893 [inline]
 do_fault mm/memory.c:6027 [inline]
 do_pte_missing mm/memory.c:4550 [inline]
 handle_pte_fault mm/memory.c:6411 [inline]
 __handle_mm_fault mm/memory.c:6549 [inline]
 handle_mm_fault+0x16cb/0x2e70 mm/memory.c:6718
 faultin_page mm/gup.c:1126 [inline]
 __get_user_pages+0x1290/0x1f10 mm/gup.c:1428
 populate_vma_page_range mm/gup.c:1860 [inline]
 __mm_populate+0x242/0x390 mm/gup.c:1963
 mm_populate include/linux/mm.h:4137 [inline]
 vm_mmap_pgoff+0x23b/0x2d0 mm/util.c:586
 ksys_mmap_pgoff+0xc1/0x310 mm/mmap.c:606
 x64_sys_call+0x14df/0x3020 arch/x86/include/generated/asm/syscalls_64.h:10
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0x12c/0x3b0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

read to 0xffffffff86e07a00 of 8 bytes by task 8291 on cpu 0:
 mem_cgroup_flush_stats_ratelimited+0x29/0x50 mm/memcontrol.c:743
 count_shadow_nodes+0x6a/0x250 mm/workingset.c:692
 do_shrink_slab+0x63/0x660 mm/shrinker.c:382
 shrink_slab_memcg mm/shrinker.c:553 [inline]
 shrink_slab+0x545/0x8f0 mm/shrinker.c:631
 shrink_node_memcgs mm/vmscan.c:6173 [inline]
 shrink_node+0x6d4/0x20a0 mm/vmscan.c:6215
 shrink_zones mm/vmscan.c:6454 [inline]
 do_try_to_free_pages+0x408/0xc90 mm/vmscan.c:6516
 try_to_free_mem_cgroup_pages+0x201/0x420 mm/vmscan.c:6838
 try_charge_memcg+0x373/0xa10 mm/memcontrol.c:2618
 charge_memcg+0x6d/0x120 mm/memcontrol.c:5006
 mem_cgroup_swapin_charge_folio+0xcc/0x150 mm/memcontrol.c:5092
 __swap_cache_prepare_and_add+0x69/0x4a0 mm/swap_state.c:476
 swap_cache_alloc_folio+0xa2/0x120 mm/swap_state.c:552
 swap_cluster_readahead+0x35c/0x3c0 mm/swap_state.c:745
 swapin_readahead+0xde/0x840 mm/swap_state.c:901
 do_swap_page+0x31e/0x2180 mm/memory.c:4875
 handle_pte_fault mm/memory.c:6414 [inline]
 __handle_mm_fault mm/memory.c:6549 [inline]
 handle_mm_fault+0xb2e/0x2e70 mm/memory.c:6718
 do_user_addr_fault+0x62f/0x1050 arch/x86/mm/fault.c:1334
 handle_page_fault arch/x86/mm/fault.c:1474 [inline]
 exc_page_fault+0x62/0xa0 arch/x86/mm/fault.c:1527
 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:618

value changed: 0x00000000ffffca37 -> 0x00000000ffffca38

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 UID: 0 PID: 8291 Comm: syz.7.1320 Tainted: G        W           syzkaller #0 PREEMPT(full) 
Tainted: [W]=WARN
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026
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